Leder



A. VON ZEERLEDER.

ELECTRIC RESISTANCE HEATER FOR. MELTING FURNACES.

APPLICATION FILED 05022. I919.

1,367,442. Patented Feb. 1,1921.

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ALFRED VON ZEERLEDER, OF GENEVA, SWITZERLAND, ASSIGNOR '10 SOCIETE KNONYME DES ATELIEBS DE SECHERON, 0F GENEVA, SWITZERLAND.

ELECTRIC-RESISTANCE HEATER FOR MELTING-FURNACES.

Specification 01 Letters Patent.

Patented Feb. 1, 1921.

Application filed December 22, 1919. Serial No. 348,629.

To all whom it may concern:

Be it known that I, ALFRED voN ZEER- LEDER, a citizen of the Swiss Republic, and resident of Geneva, Switzerland, engineer, have invented new and useful Improvements in Electric-Resistance Heaters for Melting-Furnaces, of which the following is a full, clear, and exact specification. v

The present invention relates to improvements in electric resistance "heaters for melting furnaces of the kind wherein amoldable heating body of a resistance material stable at high temperatures is employed in combination with embedded rod-like electrodes of similar material for the supply of current to said heating body. The object of the invention is to adapt the resistance heater to threephase current supply and to this end the resistanceheating ody inclosing like a jacket the melting furnace is divided into three separate segments, corresponding to the current phases, WlllCh are insulated from one another and are connected at one end to current supply poles, while at the other end they terminate in a continuous annular part of the resistance heating body.

The connection of the current poles to the heating segments is effected, as in the con Fig. 2 is a horizontal section thereof.

1 indicates the resistance heater of moldable resistance material stable at high temperatures, which, with the interposition of the electrically non-conducting layer 2, incloses the melting crucible 2, andwhich is divided into three separate segments corres onding to the three phases of the current.

he said segments of the heating body terminate at their lower ends in a continuous annular part 1-of the resistance heating body and atthe upper part they are electrically connected to the three current supply poles 3. The entrance and exit of the current take place at the current supply poles 3, while the annular part 1" constitutes the common connection'of the three-phase circuit which can be connected to the transformer.

partitions being arranged between The connection of the current poles 3 with the heater segments is effected through the medium of the rod-like electrodes 4c, which extend far enough into the mass of the said segments to insure a permanent eflicient transfer of current at these parts.

The heating segments 1 are insulated from one another over their whole length by means of insulating ribs or partitions 5 which engage between them and are for example constituted of masonry; as an additional means of insuring their mutual insulation vertical insulating plates 7, of mica or asbestos, for example, may be inserted through the said ribs and the masonry jacket 6, although such insulating plates are not absolutely necessary.

What I claim is:

1. In an electrical resistance heater for melting furnaces, adapted for threephase current supply, the combination with a melting crucible of a heating body of stable resistance material surrounding the melting crucible, said heating body being divided into three separate segments corresponding to the current phases, electrically insulating said segments and the latter being connected at one end to current supply poles, while at the other end they terminate in a continuous annular part of the re istance heating body, substantially as described.

2. In an electrical resistance heater for melting furnaces, adapted for threephase current supply, the combination. with a melting crucible of a heating body of stable resistance material surrounding the melting crucible and an intermediate electrically non-conducting layer, said heating body being divided into three separate segments corresponding to the current phases, electrically insulating partitions being arranged between said segments and the latter being connected at one end to. current supply poles, while at the other end they terminate in a continuous annularpart of the resistance heating body, substantially as described.

In witness whereof I have hereunto signed my name this 28 day of November, 1919, in the presence of two subscribing witnesses.

DR. ALFRED VON ZEERLEDER.

Witnesses Loms MUNICE, Z. GUILLOUX. 

